The strength, anti-friction and high wear resistance properties of Al.sub.2 O.sub.3 ceramics make them ideal for use in the construction of artificial protheses and orthopedic devices. The biological inactivity of Al.sub.2 O.sub.3 ceramic surfaces, however, makes it extremely difficult, if not impossible, to achieve cement-free implantation of the prothesis since bone tissue will not bond or grow thereon.
Various techniques have recently been suggested for activating the ceramic surfaces in order to enhance the bone-tissue bonding capabilities of the Al.sub.2 O.sub.3 prothesis. However, all of these techniques are either extremely expensive and time-consuming or result in ceramic structures of decreased mechanical strength, anti-friction properties and wear resistance.
It is an object of the present invention to provide a cement-free bone prothesis implant comprising a bioactive Al.sub.2 O.sub.3 ceramic and a method for the preparation thereof which is inexpensive and does not result in a decrease of the mechanical strength, anti-friction and wear resistance properties of the Al.sub.2 O.sub.3 ceramic material.